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排序方式: 共有1256条查询结果,搜索用时 15 毫秒
1.
R N Chunge P N Karumba N Nagelkerke N Kaleli M Wamwea N Mutiso E O Andala S N Kinoti 《East African medical journal》1991,68(2):112-123
A cross-sectional survey of intestinal parasitic infection in a rural community, Nderu, in Kiambu District, Kenya, was carried out in 1985 by examining 1129 individuals from 203 households (about 25% of the total population). This was followed by 3 more cross-sectional surveys, in January, May and October 1986, of 56 families comprising 461 individuals, who had also participated in the first survey. In the first survey, 81.4% of the sample was positive for at least one intestinal parasite and 78% was positive for intestinal protozoa. 72.7% of those infected had multiple infections. The prevalence of most of the protozoa increased with age but that of Giardia lamblia peaked in the 0 to 4 year class at 35.5%. Females were infected more often with several of the protozoa, but males with Ascaris. People living in larger households were more often infected with Entamoeba histolytica and Iodamoeba butschlii, while the opposite was true of H. nana and tended to be for Giardia. Significant positive associations between parasite species were common at all surveys, especially among the amoebae. The majority of negative associations were for Giardia. Unformed stools were significantly associated with Giardia, Blastocystis, and trophozoites of Trichomonas hominis and Chilomastix mesnili. Endolimax nana and Entamoeba coli were found more often in formed stools. Estimates of daily incidence, and duration of infection in days, were calculated for 11 parasites. The longest mean estimated duration of infection for any species was 237 +/- S.D. 151.4 days for H. nana and the shortest was 41.6 +/- S.D. 0.4 days for T. hominis. 相似文献
2.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
3.
E D Kroese G Bannenberg P Dogterom A B Noach J F Nagelkerke J H Meerman 《Biochemical pharmacology》1990,40(8):1885-1892
Freshly isolated rat hepatocytes were used to study the mechanism of cell death induced by N-hydroxy-2-acetylaminofluorene (N-OH-AAF). Exposure to 1.0 mM N-OH-AAF resulted in more than 90% cell death (as measured by LDH leakage) of hepatocytes isolated from male rats within 6 hr. Only 36% of the hepatocytes isolated from female rats died within this period. When inorganic sulfate was omitted from the incubation medium, a 6 hr exposure to 1.0 mM N-OH-AAF resulted in only 40% cell death of male hepatocytes. These findings are in accordance with the sex difference and sulfation dependence of N-OH-AAF hepatotoxicity observed in the rat in vivo. N-OH-AAF decreased glutathione (GSH) in male hepatocytes in a concentration-dependent manner. This GSH consumption was only partly dependent on the presence of inorganic sulfate. No lipid peroxidation was observed during N-OH-AAF exposure; N-OH-AAF even prevented endogenous and diethyl maleate (DEM)-induced lipid peroxidation. No reduction of free protein thiol groups was found after exposure to N-OH-AAF, even after 75% cell death had occurred. A reduction of protein thiols after N-OH-AAF exposure was observed in GSH depleted hepatocytes (obtained by DEM plus vitamin E pretreatment). Under these conditions N-OH-AAF-induced cell death occurred earlier. Therefore, GSH protects against protein thiol depletion by N-OH-AAF in control cells. N-OH-AAF-induced cell death was preceded by a loss of intracellular ATP. It is concluded, therefore, that neither lipid peroxidation nor depletion of protein thiols, but possibly loss of intracellular ATP, is involved in the sulfation-dependent cytotoxic mechanism of N-OH-AAF in isolated rat hepatocytes. 相似文献
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5.
D. Chemla P. Démolis M. Thyrault D. Annane Y. Lecarpentier and JF Giudicelli 《Fundamental & clinical pharmacology》1996,10(4):393-399
Summary— The influence of local resistance and cardiac performance on peripheral blood acceleration was investigated in 14 healthy male volunteers. Steady and pulsatile flow was studied in the brachial and in the common carotid arteries, ie, two territories that exhibit marked differences in resistive characteristics. Instantaneous blood velocity (V), mean blood velocity (Vm ) and artery diameter (D) were evaluated at rest by an ultrasonic range-gated pulsed Doppler flowmeter using a double transducer probe, thus allowing the calculation of mean blood flow (Q). Mean local resistance (R) was obtained by dividing the mean arterial pressure by Q. The peak value of the local acceleration of the blood was obtained by computer-assisted calculation of the first derivative of instantaneous blood velocity (Gmax = +dV/dtmax ). Peak aortic blood acceleration (GAo) was simultaneously measured from the suprasternal notch using a pulsed Doppler velocity meter. In the brachial and the common carotid arteries, Gmax was of a similar magnitude (551 ±30 and 555 ± 44 cm/s2 , respectively) despite major differences in the respective D, Vm , Q and R values. In neither artery was there a relationship between Gmax and either resting Q or R. At the brachial artery level, Gmax was positively related to GAo ( r = 0.79, P = 0.0008). At the common carotid artery level, there was a weak, although non significant relationship between Gmax and GAo ( P = 0.08). Our results indicate that the local acceleration of peripheral blood flow in the brachial artery is related rather to upstream central impulse than to downstream hemodynamics, and suggest some regional differences in the hemodynamic determinants of the local acceleration of peripheral blood flow. 相似文献
6.
In a prospective, randomized, double-blind study, 49 patients underwent lumbar myelography using iotrol (24 patients) or metrizamide (25 patients). The diagnostic imaging adequacy of iotrol was comparable with that of metrizamide. After iotrol myelography, adverse reactions were fewer, less severe, and of shorter duration than were those following metrizamide myelography. Thirteen of 24 patients (54%) receiving iotrol reported some adverse reactions compared with 24 of 25 patients (96%) receiving metrizamide. Five moderate and one severe adverse reaction occurred in the group receiving iotrol. Fourteen moderate and eight severe adverse reactions occurred in the group receiving metrizamide. Thirty-eight patients underwent electroencephalography both before and after myelography (19 iotrol and 19 metrizamide). None of the EEGs obtained after iotrol myelography changed from baseline, while seven of the EEGs obtained after metrizamide myelography showed changes from baseline. Iotrol was judged superior to metrizamide as a contrast medium in this patient population. 相似文献
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Chronic exposure of humans to benzene (BZ), a myelotoxin, causes aplastic anemia and acute leukemia. The stromal macrophage that produces interleukin-1 (IL-1), a cytokine essential for hematopoiesis, is a target of BZ's toxicity. Monocyte dysfunction and decreased IL-1 production have been shown to be involved in aplastic anemia in humans. Hydroquinone (HQ), a toxic bone marrow (BM) metabolite of BZ, causes time- and concentration-dependent inhibition of processing of the 34-Kd pre-interleukin-1 alpha (IL-1 alpha) to the 17-Kd mature cytokine in murine P388D1 macrophages and BM stromal macrophages, as measured by Western immunoblots of cell lysate proteins using a polyclonal rabbit antimurine IL-1 alpha antibody. HQ over a 10-fold concentration range had no effect on the lipopolysaccharide (LPS)-induced production of pre- IL-1 alpha precursor or on cell viability or DNA and protein synthesis. Stromal macrophages obtained from the femoral BM of C57Bl/6 mice exposed to BZ (600 or 800 mg/kg body weight) for 2 days were incapable of processing the 34-Kd pre-IL-1 alpha to the mature 17-Kd cytokine when stimulated in culture with LPS. Stromal macrophages from mice coadministered BZ and indomethacin, a prostaglandin H synthase (PHS) inhibitor that has been shown to prevent BZ-induced myelotoxic and genotoxic effects in mice when coadministered with benzene were able to convert the pre-IL-1 alpha to mature cytokine. Administration of recombinant murine IL-1 alpha (rMuIL-1 alpha) to mice before a dose of BZ that causes severe depression of BM cellularity completely prevents BM depression, most probably by bypassing the inability of the stromal macrophage in BZ-treated animals to process pre-IL-1 alpha to the mature cytokine. 相似文献
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10.
Pernes JM; Vitoux JF; Brenoit P; Raynaud A; Parola JL; Roth JP; Angel CY; Fiessinger JN; Roncato M; Gaux JC 《Radiology》1986,158(2):481-485
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs. 相似文献